/*
 * Copyright (C) 2005 - 2013 MaNGOS <http://www.getmangos.com/>
 *
 * Copyright (C) 2008 - 2013 Trinity <http://www.trinitycore.org/>
 *
 * Copyright (C) 2010 - 2013 ArkCORE <http://www.arkania.net/>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "gamePCH.h"
#include "Creature.h"
#include "MapManager.h"
#include "Opcodes.h"
#include "ConfusedMovementGenerator.h"
#include "DestinationHolderImp.h"
#include "VMapFactory.h"

#ifdef MAP_BASED_RAND_GEN
#define rand_norm() unit.rand_norm()
#define urand(a, b) unit.urand(a, b)
#endif

template<class T>
void ConfusedMovementGenerator<T>::Initialize (T &unit)
{
    const float wander_distance = 11;
    float x, y, z;
    x = unit.GetPositionX();
    y = unit.GetPositionY();
    z = unit.GetPositionZ();

    Map const* map = unit.GetBaseMap();

    i_nextMove = 1;

    bool is_water_ok, is_land_ok;
    _InitSpecific(unit, is_water_ok, is_land_ok);

    for (uint8 idx = 0; idx <= MAX_CONF_WAYPOINTS; ++idx)
    {
        float wanderX = x + wander_distance * (float) rand_norm() - wander_distance / 2;
        float wanderY = y + wander_distance * (float) rand_norm() - wander_distance / 2;
        Trinity::NormalizeMapCoord(wanderX);
        Trinity::NormalizeMapCoord(wanderY);

        float new_z = map->GetHeight(wanderX, wanderY, z, true);
        if (new_z > INVALID_HEIGHT && unit.IsWithinLOS(wanderX, wanderY, new_z))
        {
            // Don't move in water if we're not already in
            // Don't move on land if we're not already on it either
            bool is_water_now = map->IsInWater(x, y, z);
            bool is_water_next = map->IsInWater(wanderX, wanderY, new_z);
            if ((is_water_now && !is_water_next && !is_land_ok) || (!is_water_now && is_water_next && !is_water_ok))
            {
                i_waypoints[idx][0] = idx > 0 ? i_waypoints[idx - 1][0] : x;          // Back to previous location
                i_waypoints[idx][1] = idx > 0 ? i_waypoints[idx - 1][1] : y;
                i_waypoints[idx][2] = idx > 0 ? i_waypoints[idx - 1][2] : z;
                continue;
            }

            // Taken from FleeingMovementGenerator
            if (!(new_z - z) || wander_distance / fabs(new_z - z) > 1.0f)
            {
                i_waypoints[idx][0] = wanderX;
                i_waypoints[idx][1] = wanderY;
                i_waypoints[idx][2] = new_z;
                continue;
            }
        }
        else          // Back to previous location
        {
            i_waypoints[idx][0] = idx > 0 ? i_waypoints[idx - 1][0] : x;
            i_waypoints[idx][1] = idx > 0 ? i_waypoints[idx - 1][1] : y;
            i_waypoints[idx][2] = idx > 0 ? i_waypoints[idx - 1][2] : z;
            continue;
        }
    }

    unit.SetUInt64Value(UNIT_FIELD_TARGET, 0);
    unit.SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_CONFUSED);
    unit.CastStop();
    unit.StopMoving();
    unit.RemoveUnitMovementFlag(MOVEMENTFLAG_WALKING);
    unit.AddUnitState(UNIT_STAT_CONFUSED);
}

template<>
void ConfusedMovementGenerator<Creature>::_InitSpecific (Creature &creature, bool &is_water_ok, bool &is_land_ok)
{
    is_water_ok = creature.canSwim();
    is_land_ok = creature.canWalk();
}

template<>
void ConfusedMovementGenerator<Player>::_InitSpecific (Player &, bool &is_water_ok, bool &is_land_ok)
{
    is_water_ok = true;
    is_land_ok = true;
}

template<class T>
void ConfusedMovementGenerator<T>::Reset (T &unit)
{
    i_nextMove = 1;
    i_nextMoveTime.Reset(0);
    i_destinationHolder.ResetUpdate();
    unit.StopMoving();
}

template<class T>
bool ConfusedMovementGenerator<T>::Update (T &unit, const uint32 &diff)
{
    if (!&unit)
        return true;

    if (unit.HasUnitState(UNIT_STAT_ROOT | UNIT_STAT_STUNNED | UNIT_STAT_DISTRACTED))
        return true;

    if (i_nextMoveTime.Passed())
    {
        // currently moving, update location
        Traveller<T> traveller(unit);
        if (i_destinationHolder.UpdateTraveller(traveller, diff))
        {
            if (i_destinationHolder.HasArrived())
            {
                // arrived, stop and wait a bit
                unit.ClearUnitState(UNIT_STAT_MOVE);

                i_nextMove = urand(1, MAX_CONF_WAYPOINTS);
                i_nextMoveTime.Reset(urand(0, 1500 - 1));          // TODO: check the minimum reset time, should be probably higher
            }
        }
    }
    else
    {
        // waiting for next move
        i_nextMoveTime.Update(diff);
        if (i_nextMoveTime.Passed())
        {
            // start moving
            ASSERT(i_nextMove <= MAX_CONF_WAYPOINTS);
            const float x = i_waypoints[i_nextMove][0];
            const float y = i_waypoints[i_nextMove][1];
            const float z = i_waypoints[i_nextMove][2];
            Traveller<T> traveller(unit);
            i_destinationHolder.SetDestination(traveller, x, y, z);
        }
    }
    return true;
}

template<class T>
void ConfusedMovementGenerator<T>::Finalize (T &unit)
{
    unit.RemoveFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_CONFUSED);
    unit.ClearUnitState(UNIT_STAT_CONFUSED);
    if (unit.GetTypeId() == TYPEID_UNIT && unit.getVictim())
        unit.SetUInt64Value(UNIT_FIELD_TARGET, unit.getVictim()->GetGUID());
}

template void ConfusedMovementGenerator<Player>::Initialize (Player &player);
template void ConfusedMovementGenerator<Creature>::Initialize (Creature &creature);
template void ConfusedMovementGenerator<Player>::Finalize (Player &player);
template void ConfusedMovementGenerator<Creature>::Finalize (Creature &creature);
template void ConfusedMovementGenerator<Player>::Reset (Player &player);
template void ConfusedMovementGenerator<Creature>::Reset (Creature &creature);
template bool ConfusedMovementGenerator<Player>::Update (Player &player, const uint32 &diff);
template bool ConfusedMovementGenerator<Creature>::Update (Creature &creature, const uint32 &diff);
